Newbie to Avisynth.."educate me!"

[buhce]

Hello there,

I've recently decided to try my hand at Avisynth and CCE to back up my DVDs.I was previously using TMPGenc, most of my understanding of it as been from a trial and error basis, as I am one of those unfortunate people that need things explaining to them fairly simply. As I started on fairly simple scripts and encoding my first DVDs using these scripts all things seemed well. I was encoding mainly PAL at the time-I was pleased with the results.The script I was using was:

bicubicresize(720,576)
ConvertToYUY2

basically that was it. Now I was under the impression, that by doing this, it copied from you source exactly and that the only thing that would change would be the bitrate I allocated it.But I encountered something that made me think twice, this time with NTSC. Using the same script except a different res', I encoded my video and all seemed fine. Fine until I played it back on my TV.There seemed to be a problem.A jittery field order type effect was happening around on screen motion. I looked into this problem and found it to meet the charateristics of 'Hybrid Video'.Now this got me confused.For if the original DVD is hybrid and it plays fine and all I am doing, by using that simple script is, duplicating the information off the original then why, wouldn't, my duplicate play fine? Or am I just thinking about this the wrong way? No doubt I have no idea what I am talking about, so please, someone,educate me!-but simplify it.

thanks for your patience :)

[Si]

try

bicubicresize(720,480)
ConvertToYUY2

or

separatefields()
bicubicresize(720,288)
weave()
ConvertToYUY2



depending on what you trying to do

regards
Simon

[buhce]

Thanks for you reply, though it hasn't really cleared up my problems or my questions.Nevertheless, I soldier on trying desperately to get this right on the screen and right,in my head.
Using the telecide and decimate commands , I have managed to solve some portion of the DVD - to save time I haven't checked or encoded the entire video, yet .Only a small sum of it.What I have is a TV show which appears to be 3:2 in certain area's, it's obviosly an NTSC disc and it's causing me particular trouble near the end.Where I am having particular trouble is with the rolling credits.Where as the majority seems to be able to fit, "telecide(guide=1)" the end credits do not 'causing them to appear extremely jerky,flickery and present the aspect of field order error. This is what I have so far, simplistic as it is:

telecide(order=1,guide=1,post=1,gthresh=10,vthresh=36)
decimate(mode=1,threshold2=10.0)
bicubicresize(480,480)
ConvertToYUY2()

Now to those of you that actually know what you are doing, I'm sure you may have some suggestions on how to improve this-or at least I hope you do.

[Leak]

Originally posted by buhce
Where as the majority seems to be able to fit, "telecide(guide=1)" the end credits do not 'causing them to appear extremely jerky,flickery and present the aspect of field order error.

Well, for those kinds of credits I'm using the following:


b=b.Telecide(order=1)
b=b.Decimate(cycle=5)
b=b.TomsMoComp(1,5,1)


That is, I use telecide to get the action behind the rolling credits to be smooth (if you have anything playing behind them, that is) and then use TomsMoComp to make the text look right (i.e. to fix the field order)...

Works good for me. Of course, that'll keep the scrolling a bit jerky as ever 5th frame of it will be missing, but I can live with that.

If it's just 30FPS rolling text, just using TomsMoComp or some other Deinterlacer followed by a ChangeFPS(23.976) might be what you want.

np: Luomo - What Good (The Present Lover)

[buhce]

Do I use what you have suggested, as an addition to my own script?

[Bogalvator]

First off, for interlaced clips you should use ConvertToYUY2(interlaced=true) - this includes hybrid clips.

To clarify: your source is a DVD and your intended use is for it to be viewed on your TV? If so it seems to me that Telecide & Decimate shouldn't be necessary in this situation.

Are you converting between PAL and NTSC? If not, then how come you are resizing?

[buhce]

Thanks for your reply.

I am not converting from PAL to NTSC,no. The reason the resize command was used, is really down to my lack of knowledge on the subject.All, the tutorials I have read, seem to have used it, so I thought it was mandatory.

The problem:
My intended use, is for it to be veiwed on both computer and TV.The source is an NTSC DVD.I ran it through DVD2AVI to create my, .d2v file.The stats on DVD2AVI told me , it's NTSC, interlaced and 29.976.So, with that information in hand and never having any problem like this before, I frameserved it to CCE using:
bicubicresize(720,480)
ConvertToYUY2()

I then later created a DVD and began to watch it on my TV. As I did, I found it to be un-watchable, as when people moved (or there was a lot of motion), there would be a "flickery motion" around that object or objects.I was confused to why this would be. I had always thought that because a DVD had already been encoded so that it would play fine on a TV, then re-encoding it, using software such as avisynth and CCE would just be a duplication of that already optimised , original DVD . This lack of understanding of the process of what actually happens, when re-encoding from DVD was not made any easier, when I noticed that on the very same DVD I had made that contained the "flickery-motion" picture, some separate footage , different in nature, (might have been shot on DV)but from the the same original DVD, was fine.So, I began to investigate into why this could be.Not really understanding many of the possible answers I found, I tried them anyway - to save discs I then began to use the following script, so I could test them out via CDRW:

bicubicresize(480,480)
ConvertToYUY2()

So, I would be testing out numberous scripts, reading about other peoples problems trying to think for myself on the matter - some came close, but none of them worked fully. You see, the main portion of the footage, which seemed to fit the characteristics of footage that has been telecined, I could get to play quite well, using various, telecide and decimate settings.However some other parts for example, the rolling credits, were purely interlaced and didn't react well to the changes I was making.I began this DVD about 3 weeks ago and have been working on finding a solution ever since.Although, as it has gone on, finding a solution has begun to take a back seat to understanding and hopefully through understanding, I can find my solution.As my questions are fairly basic and seem even a bit dumb even to me, I fear that no one will answer them or being linked to informative but breathless tutorials and guides, unable to answer when I ask.

If you need anymore information, please feel free to ask.

Thank you for your time and patience :)

[Si]

Now we've a bit more info :)

If interlaced video looks strange on a TV it is usually because of field order problems.

In CCE, there should be a setting for field order, and basically you should set it to the opposite of your current setting (I don't have CCE so I don't know what they call it - but it will/should have a setting marked field orderA/B or Odd/Even or Top Field First/Bottom Field First.

regards

Simon

[buhce]

Would doing as you suggested have the same effect as, "swapfields()"?
If so, I have tried that and it didn't work. As for selecting a field order, I can't seem to find that in CCE - I have version 2.67.
I did however, try this in tmpgenc. It still didn't cure the problem.

[Si]

Looking back at your original post where you say you used TMPGEnc to produce DVD's.

Does your old method work on this NTSC DVD and what was it?

regards
Simon

[buhce]

Thanks for the response
My old method was to create a .d2v file of the dvd, load that into tmpgenc then in settings>advanced input the correct information : Video source type
Field order
source aspect ratio
Video arrange method

Then under the video tab I was set all the correct information depending the type of video, I wanted to create.Then select ES(video only) then encode it. This method also created the same problem.

[Si]

So its not an avisynth problem then :)

regards
Simon

[buhce]

what sort of problem is it?

[Si]

A very good question:)

Maybe you should try posting a question in one of the general forums or a CCE forum but I'd supply full details of exactly what and why your trying to do :)

regards
Simon

[Abond]

Hi, buhce
As I understand you try to make a copy of this DVD to DVD, then you should only reauthor the files from the original DVD, and burn - you don't need Avisynth. Even if you want to shrink the files size there are quite good programs to do this without Avisynth - for example Rejig or DVDShrink (literary!). Well, probably a lot other programs...